Bridge rectifiers consist of four, six or seven diodes and/or thyristors. They are available in current ranges between 50 A and 200 A and voltage ranges between 600 V and 1,800 V.
Many bridge rectifiers feature an insulated, metal base plate to provide effective cooling. The base should be connected to a cooling structure via a highly heat-conductive surface, such as Kerafol thermally conductive films, for example. If the insulating voltage is not sufficient, it can be increased further using Kerafol films.
If a current flows through a semiconductor, losses occur. In simple diodes, the losses are calculated by multiplying the current by the forward bias (z.B. 0.7V) P = 0.7V * I. If a 1 A current is flowing, 0.7 W of power is converted into heat in the diode. This heat must be dissipated in order not to damage the diode. This presents a challenge with currents possibly reaching 200 A. The heat is dissipated on the base plate via the silicon thermal connection with the help of ceramic. Electric insulation must also be provided since voltages up to 1,800 V may occur at the same time. The air and leakage paths need to be optimized to allow small housing. This is achieved with a silicon compound.